We have developed an exercise designed to give students practice calculating arterial O2 content, O2 delivery, physiological dead space, dead space and alveolar ventilation, and alveolar partial pressure of O2 and CO2. The exercise is in the form of…
To determine the correlation between ultrastructural and physiological changes in blood-gas barrier function in lungs transiently exposed to very high vascular pressures, we increased capillary transmural pressure (Ptm) of 6 canine isolated perfused…
We determined the time course of changes in extravascular lung water (EVLW) that occur after massive sympathetic activation produced by intracisternal veratrine administration in chloralose-anesthetized dogs. Three groups of dogs were studied. In the…
We evaluated the ability of a group of male runners (n = 4) to do maximal and submaximal exercise before and after they ran a competitive marathon (42.2 km) race. VO2max was determined 3 to 6 times in each runner, on alternate days, 1-4 weeks prior…
The elevation of venous pressure (Pv) in isolated perfused organs causes organ weight to increase in a biphasic manner. The initial rapid phase results primarily from an increase in blood volume (BV), whereas the second slower phase is generally…
We determined whether the solvent drag reflection coefficient (sigma f) for total proteins of a canine perfused left lower lung lobe (LLL) preparation decreases at elevated venous pressures (Pv). We found that sigma f (estimated using the…
The solvent drag reflection coefficient (sigma) for total proteins can be estimated by comparing the relative degrees of concentration of erythrocytes and plasma proteins that occur during fluid filtration in an isolated perfused organ. In this…
Previous studies have suggested that papaverine, a drug commonly used in studies of transvascular fluid and solute exchange to eliminate confounding effects of changes in vascular tone, may itself increase vascular permeability. In this study, we…
Positive inspiratory pressure- (PIP) ventilated, isolated rat lungs become edematous when perfused at rates approximately the normal cardiac output. The study was conducted to test the hypothesis that high peak inspiratory pressures contribute to the…
We sought to determine whether catecholamines are responsible for the depressed left ventricular (LV) function that follows massive sympathetic nervous system (SNS) activation and whether the additional myocardial energy demands of
The objective of this study was to determine whether myocardial contractility is depressed by intense activation of the sympathetic nervous system. A massive sympathetic discharge was produced by injecting veratrine or sodium citrate into the…
We evaluated the effect of systemically administered histamine on coronary vascular permeability (CVP) of pentobarbital-anesthetized, open-chest dogs with and without beta-receptor blockade. We determined changes in CVP by comparing prenodal cardiac…
This study was undertaken to determine whether endothelium-derived relaxing factor (EDRF) modulates the pulmonary and systemic hemodynamic responses to massive sympathetic nervous system (SNS) activation and, in so doing, also modulates the degree of…
Whether two copies of the neurotrophin-3 (NT3) gene are necessary for proper development of cardiac sympathetic innervation was investigated in mice carrying a targeted inactivation of the NT3 gene. Heterozygous (+/-) and null (-/-) mutant mice had…
